1. Field of the Invention
The present invention relates to a tree felling apparatus having a curved saw blade substantially corresponding to a portion of a sphere. The invention is also directed to saw tooth adapted to be removably mounted at the periphery of the saw blade.
2. Prior Art
Canadian Pat. Nos. 983,825, 994,647 and 1,017,232 describe tree felling apparatus using a curved saw blade. In each of these cases, the saw blade is rotated through a power means acting on its periphery. Furthermore, the saw blade is actuated through a pendulum movement in the direction of the tree to be cut.
Canadian Pat. Nos. 1,012,038 and 1,074,212 disclose saw tooth of various shapes and uses. The tooth described in Canadian Pat. No. 1,012,038 have a curved face which is not oriented in the direction of travel of the blade or the chain, that is, the radius of curvature of the concave portion is not intended to be oriented in the tangential direction of the saw. The saw teeth are not square and do not need to be square. The same applies to Canadian Pat. No. 1,074,212 which has a tapered shape in order to provide free space between the work piece and the saw blade.
In U.S. Pat. Nos. 1,459,805 and 1,838,520 cutting tools are disclosed for use in turning, planing or boring tools. The cutter in such tools is provided with a concaved shape adjacent a tapered side but the cutter does not travel in a direction so that the radius of the concave surface remains parallel to the tangent of the blade.